Question: Rewrite ${((5^{-9})(8^{-10}))^{10}}$ in the form ${5^n \times 8^m}$.
${ ((5^{-9})(8^{-10}))^{10} = (5^{(-9)(10)})(8^{(-10)(10)})} $ ${\hphantom{ ((5^{-9})(8^{-10}))^{10}} = 5^{-90} \times 8^{-100}} $